CI: install ninja on windows

The new CI images provided by GitHub no longer provide ninja.exe, so
this commit installs it explicitly, using the suggested method from
GitHub.

See https://github.com/actions/runner-images/issues/8343 for more
details.
0345d78663Andrew Kelley committed on 9/21/2023, 9:18:55 PMparent00f4290
2 files changedLine totals unavailable